Engine starter



March 1, 1960 L. J. HAMMAN ENGINE STARTER 4 Sheets-Sheet 1 Filed Feb.11. 1957 mvsmon [J45 d. HAM/1AM ATTORNEY March 1, 1960 L. J. HAMMANENGINE STARTER 4 Sheets-Sheet 2 Filed Feb. 11, 1957 INVENTOR V Ans JHAMMAA/ BY\ LWMMM' ATTORNEY March 1, 1960 L. J. HAMMAN ENGINE STARTERFiled Feb. 11, 1957 4 Sheets-Sheet 3 I INVENTOR .6 v.45 HflMM/I/VATTORNEY March 1, 1960 L. J. HAMMAN 2,926,648

ENGINE STARTER 4 Sheets-Sheet 4 Filed Feb. 11, 1957 INVENTOR Z n: JA/J/V/VA/V ATTORNEY United States Patent ENGINE STARTER Lyle I. Hamman,Eaton Rapids,-Mich., assignor to Eaton Stamping Company, a corporationof Michigan Application February 11, 1957, Serial No. 639,507

9 Claims. (Cl. 123-179) The present invention relates to improvements inrecoil engine starter of the type having a rope "wound upon a pulley bya spring and when the rope is pulled a clutch mechanism attached to thepulley engages a part attached to the engine for rotating the engine tostart it. When the rope is released the spring will rewind the rope uponthe pulley.

It is an object of the invention to provide a simple, inexpensive andreadily serviced starter. To this end my improved starter has beendesigned with a minimum number of component parts, all of which may bereadily assembled by unskilled persons. It trouble developsin use, suchas rope breakage, the operator may easily disassemble the starter toreplace the rope or make other necessary repairs or replacements.

Another object of the invention is to provide a starter which employsonly a single clutch dog and which makes it possible to mount thestarter upon an engine without the necessity of maintaining exactconcentricity between the engine and the starter.

Another object is to provide a starter of the type described in whichretraction of the rope and clutch dog is performed by a single spring.

Another object is to provide an improved starter of the type describedin which the clutch dog is carried directly by the pulley and engagesdirectly with the starter hub attached to the engine.

A further object is to provide a clutch dog and brake structure whichpermits a recess for the bolt head or nut attaching the starting hub tothe engine and thus reduce the overall height of the starter.

These and other objects and advantages will more fully appear from thefollowing specification and appended claims.

In the drawings,

Fig. 1 is a cross-sectional view of the starter assembly taken on line1-4 of Fig. 2, the engine being shown in dotted outline,

Fig. 2 is a top view of the starter housing and assembly shown in Fig.1,

Fig. 3 is a bottom view of the starter housing and assembly shown inFig. 2 showing the clutch dog retracted and rope fully recoiled,

Fig. 4 is a view similar to Fig. 3 showing the clutch dog projected by apull upon the rope,

Fig. 5 is a top view of the retainer cup for the clutch dog removed fromthe assembly of Fig. I,

Fig. 6 is a side-elevational view of Fig. 5,

Fig. 7 is a side view of the starter brake-removed from the assembly ofFig. 1,

Fig. 8 is a plan view of the starter pulley assembly as viewed from theside'to which the spring is attached,

Fig. 9 is a plan view of the starter pulley assembly as viewed from theside to which the retainer cup for the clutch dog is attached, theclutch dog being shown in position,

Fig. 10 is across-sectional view taken on line X-X 2 of Fig. 8 showingthe manner in which the end of the rope is anchored, and I Fig. 11 is aview taken on line Xi-- Xi of Fig. 1 showing theclutch dog projecting toengage the starter hub serrations.

Referring to the illustrated form of the invention, the starter assemblycomprises a die cast housing 10 having an inserted pin 12 upon which thepulley assembly 14 is rotatably supported. Recoil spring 16 is carriedwithin the cylindrical recess 18 of the housing 10. The starter hub 20,attached to the engine 22 by thebolt and nut 24, has serrations 26defined in the cylindrical flange 28 in opposed relation to the clutchdog 30 guided and retained by the retainer cup 32. A brake 34, attachedto the .pin 12 by the screw 36, places a drag upon the cup 32 to controlthe movement of the cup 32 relative to the pulley 14 and thus controlsthe operation of the dog 30.

The pulley assembly 14 preferably comprises a die cast pulley portion 38and a stamped sheet metal sheave portion 40. Portion 38 has twodiametrically opposed arcuate bosses upon which the retainer cup 32 ismounted and supported for limited relative rotation about the axis ofthe pin 12 upon the pulley assembly 14. This limited relative rotationis provided by arcuate slots 42 in which complementary arcuate portionsof the bosses 44 and 45 engage; screws 43 received in the bosses 44 and45 engage the ends of the slots 42 to act as stops and also function tohold the retainer cup 32 in position on the bosses 44 and 45 byoverlapping the slot defining portions of the cup 32. The drag action ofthe brake 34 upon the retainer cup 32 is obtained by the provision of aninner cylindrical flange 46 upon the cup 32 with which the resilientfingers 48 of the brake 34 engage.

To conveniently anchor the inner end of the rope 50 to the pulleyassembly 14, the pulley portion 38 has two integral ribs 52 across whichthe rope end is supported at the time the sheave 40 is assembled inposition. On the inner surface of the sheave 40 are similar formed ribs54 is slightly offset relation to the ribs 52 but located to engage theside of the rope opposed to that engaged by the ribs 52. When the sheave40 is then attached to the pulley portion 38 by the screws 56, the ropeend will be firmly anchored in the pulley assembly 14- 7 As shown inFig. 11 the dog30 takes the form of a length of flat metal stock havingone end formed into a semi-cylindrical portion 58 and received forswivel movement in the socket 60 in the boss 45. The free end 62 of thedog 30 is guided within a slot 63 in the outer flange 64 of the cup 32.Upon relative rotational movement between the boss 45 and the cup 32,the relationship between the dog 30 and the slot 63 will cause the dog30 to be either projected or retracted within the slot 63 depending uponthe direction of relative rotation of the boss 45. When the dog isprojected its outer end 66 will engage the serrations 26 of the starterhub 20 attached to the engine 22 to crank the engine in a well knownmanner. Rotation of the pulley assembly 14 in a recoiling direction willretract the dog 30 in the slot 63-due to the drag action of the brake 34on the cup 32 which momentarily holds the cup 32 stationary as therotation of the boss 45 withdraws the dog 30 from its projectedposition.

To avoid any possibility of the cup 32 shifting from one position toanother due to vibration of the engine, a light spring 68 is shownattached to the cup 32 to hold the cup in a dog retracting position. Itwill be understood that the spring 68 is too light to overcome thefunction of the brake 34.

One end of the spring 16 is attached to the housing 10 and the oppositeend is attached to the boss 70 on the pulley assembly 14 and embracesthe same within the V recess 18. To permit the spring 16 to be placedunder necessary tension to rewind the rope 50, a slot 72 is provided inthe flange 74,,of the pulley assembly to receive the end of the ropecoiled upon the pulley assembly and provide the necessary clearancebetween the housing and the flange 74 to enable the pulley assembly tobe rotated to wind up the spring 16 prior to the end of the rope 50being located within its fixed bushing in the housing 10.

Disregarding the optional tension spring 68, it will be seen that therecoil spring 16 performs the entire retraction operation. When theengine starts the action on the 'dog 30 will force the dog 30 againstthe portion of the cup 32 defining the slot 63 to move the cup 32relative to the boss 45 to retract the dog 36'. If the engine does notstart to initiate this retraction of the dog 30, the combinedfunction'of the brake 34 and spring 16 will, when the rope 50' isreleased to the action of the recoil spring 16.

By having the dog 30 directly carried on the boss 45 of the pulleyassembly 14, the operative connection between the pulley and the startercup on the engine is solely confined to the dog 30. In practice a singledog 30 has been found to be adequate although more than one dog 30 maybe used by merely duplicating the structure disclosed. The designdisclosed is characterized by the fact that it is only necessary forperformance to hold the concentricity of the starter hub 20 and pulleyassembly 14 within limits that may be readily met under ordinarymanufacturing practices.

A low overall height between the starter hub 20 and the housing 10 hasbeen made possible by the design of the cup'32 and brake 34 providingclearance for the bolt and nut attaching the hub 20 to the engine 22.

Having thus described my invention what I claim as new and desire tocover by Letters Patent is:

1. In an engine cranking device operated by withdrawing a flexiblemember wound upon a pulley, the member being rewound by a spring and therotation of the pulley being imparted to the engine through a clutchmechanism including a dog, the combination with pulley supportingstructure, a pulley and a dog pivoted upon said pulley, of a retainerfor actuating said dog to project and retract the same in the functionof the clutch mechanism, said retainer being of annular form of U-shapedcross-section with inner and outer flanges, a mounting structure for thepivotal connection of said dog located on one side of said pulley in offset relation to the axis of rotation of said pulle a guide slot in saidouter flange, said mounting structure being located within said outerand inner flanges, said dog being received in said slot and havingrelative end-wise movement therein, means attaching said retainer uponsaid pulley side for rotation of said pulley as a unit as well as forlimited relative rotation on said pulley side about said axis, brakestructure for imparting a frictional drag upon said retainer, said brakestructure being attached to said pulley supporting structure and heldagainst rotation with said pulley and having frictional engagement withsaid inner flange, and means on said side having a lost motion pin andslot connection with a portion of said retainer to drive said retaineras a unit with said pulley against the drag of said brake upon rotationof said pulley in either direction, said brake structure holding saidretainer against rotation with said pulley upon initial rotation of saidpulley in either direction within the arcuate extent of said lost motionconnection whereby the location of saidslot to the pivotal mounting ofsaid dog is altered to provide endwise projection and retraction of saiddog relative to said slot.

2. In the combination of claim 1 wherein said brake has circumferentialengagement with said inner flange to equally distribute and: apply thedrag of said brake relative to the direction of rotation of said pulley.

3. In the combination set forth in claim 2 wherein said pin and slotconnection is defined by said retainer having arcuate slots in theradial side thereof disposed between said flanges, and screws extendingthrough said slots and engaged in said mounting structure.

4. In an engine cranking device operated by withdrawing a flexiblemember woun'd' upon a pulley, the member being rewound by a spring andthe rotation of the pulley being imparted to the engine through a clutchmechanism including a dog, the combination with pulley sup portingstructure, a pulley and a dog pivoted thereon, of

means for rocking said dog into and out of engine cranking position,said means comprising a dog actuator mounted upon one side of saidpulley, means supporting said actuator for limited relative rotation onsaid pulley side about the axis of rotation of said pulley, said lastsupporting means including a lost motion drive connection between saidactuator and said pulley, said actuator having an annular outer axiallyextending flange, means pivotally supporting said dog on said pulleybetween said actuator and the axis of rotation of said pulley, a guideand cam portion in the form of a slot formed in said flange of saidactuator in which said dog is guided and rocked about its pivot andbrake means fixed upon said pulley supporting structure and engagingwith said actu ator to retard the movement of said actuator to effectrelative movement between said actuator and said pulley upon initialmovement of said pulley in either direction.

5. In an engine cranking device as defined in claim 4 said actuatorbeing in the form of an annular member of U-shaped cross-section andhaving an inner flange as well as said outer flange, said brake being inthe form of circumferentially spaced resilient fingers engaging withsaid inner flange.

6. In an engine cranking device, the combination with a spring re-coilwinder for the starting rope, a pulley and a clutch mechanism includinga dog pivoted upon said pulley, of dog actuator structure in the form ofinner and outer annular flange portions connected by a radial webportion, means projecting from a side of said pulley upon which said dogactuator is supported for limited relative movement on said pulley, apin and slot lost motion connection between said web portion and saidprojecting means, said flanges being disposed upon opposite sides ofsaid projecting means, a brake ring concentric .with the axis ofrotation of said pulley and disposed within said projecting means andengaging with said inner flange, said dog being pivoted on saidprojecting means with its pivotal axis being located between saidflanges, said dog projecting through an opening in said outer flange andbeing rocked about its pivotal axis by relative rotation between saidactuator and pulley.

7. In a engine cranking device of the type described, a separable twopart pulley upon which a rope is to be wound and unwound, hub structureon one of said pulley parts upon which the other of said pulley part ispiloted, opposed ribs defined upon said parts disposed in staggeredrelation to each other, a rope to be wound upon said pulley and havingits inner end disposed between said opposed ribs, and removable meansfor. attaching said parts together and simultaneously clamping said ropeend between said ribs.

8. In an engine cranking device, in combination with a fixed structureand a recoil spring, of a pulley to which said spring is attached at oneend to one side of the pulley with the other end of said spring attachedto said fixed structure, dog mounting means formed on the other side ofsaid pulley integral therewith, a dog pivotally supactuator and saidpulley.

' 9. In an engine cranking device, in combination, a pulley, a supporton one side of said pulley concentric with the axis of rotation of saidpulley,'an annular actuator nested on said support and rotatablerelative to said pulley in said support, a clutch dog pivotally carriedupo'n said support, said actuator having an annular flange having a slotdefined therein through which said dog is projected and retracted uponrelative movement between said actuator and said pulley, means defininga lost motion connection between said support and said actuator, and anannular brake concentric with said axis and nesting with a portion ofsaid actuator and frictionally engaging therewith.

References Cited in the file of this patent UNITED STATES PATENTS1,272,944 Green July 16, 1918 2,460,420 Kincannon Feb. 1, 1949 2,530,623Martin Nov. 21, 1950 2,564,787 Mack Aug. 21, 1951 2,592,639 Armstrong eta1 Apr. 15, 1952 2,848,987 Morden Aug. 26, 1958

